Topical phenylephrine hydrochloride is routinely administered with few safety precautions, but evidence regarding its systemic safety to date is controversial. As even short-term variations in 24-hour blood pressure (BP) and heart rate (HR) can adversely affect cardiovascular health, better evidence on phenylephrine’s effects on HR and BP is required.
To perform a meta-analysis of available evidence regarding cardiovascular adverse effects of topical phenylephrine.
PubMed, MEDLINE, and the Cochrane Database of Systematic Reviews and Clinical Trials were searched for relevant literature from January 1, 1970, to January 1, 2014, using a combination of the following search terms: topical, ocular, ophthalmic, phenylephrine, tropicamide, cardiovascular effect, side effect, blood pressure, heart rate, mydriatic, and eye drops. A total of 70 articles related to the topic were identified and all full texts were retrieved.
Randomized clinical trials reporting change in BP and HR for adults were included in this review. All studies reporting results for neonates or infants, not reporting standard deviations, or not specifying the time of measurement or the concentration of phenylephrine used were excluded.
Data Extraction and Synthesis
Data from randomized clinical trials that reported BP and/or HR as well as the time following administration of topical phenylephrine at which measurements were obtained by concentration of phenylephrine as a mean change and its standard deviation were extracted. Data were synthesized by concentration of phenylephrine and time of measurement following topical application using random-effects models with inverse variance weighting to account for heterogeneity across studies.
Main Outcomes and Measures
Difference in BP and HR after topical administration of phenylephrine.
Eight RCTs with a total of 916 participants were included. Data were available for phenylephrine, 2.5%, at 20 to 30 minutes and 60 minutes or longer after administration, and neither BP nor HR changed at either time. Following application of phenylephrine, 10%, BP increased at 5 and 10 minutes (mean difference for both, +15 mm Hg; 95% CI, 11.94-18.54; P < .001) but decreased at 20 to 30 minutes and 60 minutes or longer with no changes detected against baseline. A mean increase in HR by 4.48 beats/min (95% CI, 1.09-7.88; P = .01) was present at 20 to 30 minutes following application of phenylephrine, 10%, and HR decreased by 60 minutes or longer with no changes detected compared with baseline.
Conclusions and Relevance
Phenylephrine, 2.5%, leads to no clinically relevant change in BP or HR, and the changes in BP and HR seen with phenylephrine, 10%, are short lived. Thus, phenylephrine, 2.5%, is safe to use in clinical routine.